Development of a fast response neutron detector for the supersonic FRC collision process

Area of Science:

• Plasma Physics
• Fusion Energy Research
• Astrophysical Shockwaves

Background:

• Collisional merging of field-reversing configurations (FRC) at supersonic/Alfvénic velocities can generate shockwaves.
• Shockwaves in plasmas are theorized to accelerate particles, a mechanism relevant to astrophysical phenomena.

Purpose of the Study:

• To investigate particle acceleration by shockwaves during FRC collisional merging.
• To detect neutrons from deuterium-deuterium (D-D) fusion reactions, providing evidence of accelerated non-thermal particles.

Main Methods:

• Developed a plastic scintillation detector with high neutron sensitivity and nanosecond response time.
• Performed collisional merging experiments of FRCs at supersonic/Alfvénic velocities.
• Analyzed experimental data for neutron signals potentially indicating particle acceleration.

Main Results:

• Observed a signal consistent with neutrons during the FRC collisional merging process.
• The detected signal is not explained by adiabatic compression as predicted by magnetohydrodynamics simulations.

Conclusions:

• The detected neutron signal provides preliminary evidence for particle acceleration by shockwaves during FRC merging.
• This experimental observation challenges existing theoretical models and warrants further investigation into plasma shockwave dynamics.